Traditional drive devices that read and reproduce various information recorded on a disk recording medium such as a CD (Compact Disc) and a DVD (Digital Versatile Disc) and record various information on the disk recording medium employ an arrangement in which the disk recording medium is detachably attached to conduct reproducing and recording processing. Some of the drive devices detachably and rotatably support the disk recording medium with a turntable having so-called self-chucking function (for instance, see Patent Document 1).
The device disclosed in the Patent Document 1 has a body provided with components for reproducing a CD and a cover openable/closable relative to the body. A motor is installed in the body and a disk table is attached to a drive shaft of the motor protruding from an upper partition plate of the body. A ball chucking mechanism including a plurality of balls and a rubber ring for applying biasing pressure onto the balls is provided on a chuck portion protruding approximately at the center of the disk table. The ball chucking mechanism determines the position of the CDs attached to the chuck portion in a fixed manner. The cover is provided at a position opposing to the disk table, the cover also having a spare disk holder with a chuck portion including a ball chucking mechanism, on which a spare disk is to be attached.    [Patent Document 1] JP-A-2000-207879 (page 3 left column to page 4 right column)